CN218243253U - Motor for electric tool and electric tool - Google Patents

Abstract

The utility model relates to an electric tool technical field discloses a motor and electric tool for electric tool. A motor for electric tool includes the stator, rotor and motor shaft, the motor shaft is connected in the rotor in order can rotate along with the rotor, the motor shaft includes first portion and second portion along the first direction at least, the second portion is provided with the installation department that is used for installing the bearing, first portion is formed with the gear, second portion and motor shaft integrated into one piece, effective gear length on the first portion is L1, the bearing has the first terminal surface that is close to the gear, first portion has the second terminal surface of keeping away from the bearing, first terminal surface is L2 with the distance of second terminal surface in first direction, the ratio more than or equal to 0.4 and less than or equal to 1 of L1 and L2. The utility model discloses a motor for electric tool, compact structure, small. The utility model discloses electric tool, through setting up above-mentioned motor that is used for electric tool, overall structure is compact, small.

Description

Motor for electric tool and electric tool

Technical Field

The utility model relates to an electric tool technical field especially relates to a motor and electric tool for electric tool.

Background

Many prior art power tools employ a motor as a drive source. The motor comprises a stator, a rotor and a motor shaft. The motor shaft is connected with the rotor and rotates relative to the stator synchronously with the rotor so as to realize power output. However, in the prior art, the axial dimension of the motor shaft is not compact enough, which leads to a larger overall dimension of the motor and the electric tool, and thus the development trend of the electric tool that the size is reduced gradually cannot be satisfied.

Therefore, a need exists for a motor for a power tool and a power tool to solve the above problems.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a motor for electric tool, its compact structure, small.

Another object of the utility model is to provide an electric tool, through setting up above-mentioned motor that is used for electric tool, overall structure is compact, small.

To achieve the purpose, the utility model adopts the following technical proposal:

a motor for a power tool, comprising:

a stator;

a rotor;

a motor shaft connected to the rotor to be rotatable together with the rotor, the motor shaft including at least a first portion and a second portion in a first direction, the second portion being provided with a mounting portion for mounting a bearing, the first portion being formed with a gear;

the second part is integrally formed with the motor shaft;

the effective gear length on the first portion is L1, the bearing is provided with a first end face close to the gear, the first portion is provided with a second end face far away from the bearing, the distance between the first end face and the second end face in the first direction is L2, and the ratio of L1 to L2 is greater than or equal to 0.4 and smaller than or equal to 1.

As an alternative, the gear is formed in the first part by a cold extrusion process.

As an alternative, the motor of the electric power tool further includes a fan, the fan is disposed on the motor shaft and adjacent to the rotor, the fan has a third end surface in the first direction, the magnet of the rotor has a fourth end surface in the first direction, and the third end surface and the fourth end surface are abutted against each other in the first direction.

As an alternative, in the first direction, a portion of the fan for engaging with the motor shaft at least partially overlaps with an end plate of the stator.

A motor for a power tool, comprising:

a stator;

a rotor;

a motor shaft connected to the rotor and rotatable therewith, the motor shaft including a first portion for forming a gear;

the gear is formed by adopting a cold extrusion process.

As an alternative, the motor of the power tool further includes a fan that is disposed on the motor shaft and adjacent to the rotor, and a portion of the fan that is configured to engage with the motor shaft at least partially overlaps with an end plate of the stator in the first direction.

A motor for a power tool, comprising:

a stator;

a rotor including a body and a plurality of magnets connected to the body;

a motor shaft connected to the rotor and rotatable together with the rotor;

the fan is sleeved on the motor shaft and is arranged adjacent to the rotor;

the fan is provided with a third end surface in the first direction, the magnet is provided with a fourth end surface in the first direction, and the third end surface and the fourth end surface are abutted in the first direction.

As an alternative, in the first direction, a portion of the fan for engaging with the motor shaft at least partially overlaps with an end plate of the stator.

An electric tool comprises a body part and the motor for the electric tool, wherein the motor for the electric tool is installed on the body part.

As an alternative, the power tool further includes a power supply device detachably connected to the body portion.

The utility model discloses beneficial effect does:

the utility model discloses a motor for electric tool through adopting cold extrusion technology processing gear, or makes the third terminal surface of fan offset with the fourth terminal surface of magnet, then under the certain prerequisite of required effective gear length, can both make motor shaft and whole motor shorten along the size of first direction, has improved the compact structure nature of motor along first direction, has reduced the volume of motor.

The utility model discloses an electric tool, through setting up foretell motor that is used for electric tool, overall structure is compact, small.

Drawings

Fig. 1 is a schematic partial structural view of an electric tool according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of the power tool at the motor according to the embodiment of the present invention;

fig. 3 is an exploded view of a motor for a power tool provided by an embodiment of the present invention at one viewing angle;

fig. 4 is an exploded view of a motor for a power tool from another perspective provided by an embodiment of the present invention;

fig. 5 is a schematic structural view of a motor shaft and a bearing provided by the present novel embodiment.

In the figure:

10-a motor for a power tool; 11-a stator; 111-end plate; 112-support ring; 113-a coil; 12-a rotor; 121-a magnet; 1211-fourth end face; 122-a body;

13-motor shaft;

131-a first portion; 1311-gear; 1312-a second end face;

132-a second portion; 1321-a mounting portion;

133-a third part;

14-a bearing; 141-a first end face; 15-a fan; 151-third end face; 152-a mating portion; 16-a sleeve;

20-a body portion;

30-a transmission assembly; 31-sun gear; 32-a planetary gear; 33-an output shaft; 34-a shock absorbing assembly;

40-a gearbox housing.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures associated with the present invention are shown in the drawings, not all of them.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, detachably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. "beneath," "under" and "beneath" a first feature includes the first feature being directly beneath and obliquely beneath the second feature, or simply indicating that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

The present embodiment provides a motor 10 for a power tool and a power tool. The power tool includes a motor 10 for the power tool. In particular, the power tool may be an electric drill, a table saw, an intelligent lawn mower, and the like. In fact, the motor 10 for an electric tool provided in the present embodiment is suitable for handheld electric tools such as electric drills, electric wrenches, electric screwdrivers, electric hammer drills, electric circular saws, and sanding machines, table-type electric tools such as table saws, and outdoor tools such as lawn mowers, electric scissors, pruners, and electric saws. It should be understood that the following examples are some, but not all, of the examples of the present invention.

As shown in fig. 1 and 2, the electric power tool includes a body portion 20, a motor 10 for the electric power tool, a transmission assembly 30, and a tool (not shown). Specifically, the body portion 20 is used for a user to hold or fix on a support platform. The body portion 20 is a housing structure in which the motor 10 and the transmission assembly 30 for the electric power tool are disposed. A motor 10 for a power tool has a motor shaft 13, an input end of a drive assembly 30 is connected to the motor shaft 13, and an output end of the drive assembly 30 extends outside of a housing structure for connection to a workpiece. The rotational motion output by the motor 10 for the power tool is output to the tool through the transmission assembly 30 to move the tool. Further, the electric tool further comprises a power supply device (1) (not shown in the figure), the power supply device is detachably connected with the body part 20, the power supply device can supply power for the motor 10 of the electric tool and other electric elements of the electric tool, and when the power supply device is insufficient in electric quantity, the power supply device can be conveniently replaced with a new power supply device, so that the electric tool is more convenient to use. Specifically, the power supply device may be a battery pack, and the battery pack may be detachably connected to the body portion 20 by any one of a fastening member connection, a snap connection, a magnetic attraction fixation, and the like, which is not specifically limited herein.

As shown in fig. 2 to 4, the motor 10 for the power tool includes a stator 11, a rotor 12, a motor shaft 13, and a fan 15. The stator 11 is substantially annular in configuration and is fixed inside the body portion 20. The rotor 12 is disposed inside the stator 11 and is disposed coaxially with the stator 11, the motor shaft 13 is rotatably supported in the body 20 by a bearing 14, and the motor shaft 13 penetrates the rotor 12 and is fixedly connected to the rotor 12. The motor shaft 13 is connected to the transmission assembly 30 at one end along the axis and to the fan 15 at the other end. When the motor 10 for the electric tool is powered on, the rotor 12 rotates relative to the stator 11 to drive the motor shaft 13 to rotate, the motor shaft 13 drives the transmission assembly 30 to move so as to enable the tool to work, and meanwhile, the motor shaft 13 drives the fan 15 to rotate, so that the stator 11 and the rotor 12 are cooled and radiated.

In this embodiment, the axial direction of the motor shaft 13 is defined as a first direction, and the end of the motor shaft 13 for connecting with the transmission assembly 30 is a front end, and the end for connecting with the fan 15 is a rear end. As shown in fig. 2 and 3, the stator 11 includes a support ring 112 and a plurality of coils 113. The support ring 112 is fixedly coupled to the body portion 20, and the plurality of coils 113 are uniformly arranged on the support ring 112 along a circumferential direction of the support ring 112. As shown in fig. 2 and 4, the rotor 12 includes a main body 122 and a plurality of magnets 121, the main body 122 is rotatably connected with the support ring 112, and the plurality of magnets 121 are uniformly arranged on the main body 122 and located on a side (i.e., a rear side) of the main body 122 facing the fan 15.

In the present embodiment, as shown in fig. 2 and 5, the motor shaft 13 includes a first portion 131, a second portion 132, and a third portion 133 in order from the front to the rear. The third portion 133 is disposed through the rotor 12 and fixedly connected to the rotor 12. Specifically, the sleeve 16 is fixed on the third portion 133, and the sleeve 16 is connected with the main body 122 of the rotor 12, so as to realize the connection between the motor shaft 13 and the rotor 12. The third portion 133 passes through the end of the rotor 12 remote from the first portion 131 for mounting the fan 15. The second portion 132 of the motor shaft 13 has a larger shaft diameter than the third portion 133, the second portion 132 is provided with a mounting portion 1321, the bearing 14 for supporting the motor shaft 13 is disposed on the mounting portion 1321, and two end surfaces of the bearing 14 can abut against the transmission assembly 30 and the stator 11, respectively. First portion 131 has formed thereon a gear 1311 for driving engagement with drive assembly 30. Wherein the second portion 132 and the third portion 133 are integrally formed.

Preferably, in the present embodiment, the first part 131 is integrally formed with the second part 132, and the effective gear length on the first part 131 is L1 (i.e. the length of the gear 1311 in the first direction). The bearing 14 has a first end face 141 close to the gear 1311, the first portion 131 has a second end face 1312 far from the bearing 14, and the distance between the first end face 141 and the second end face 1312 in the first direction is L2, where a ratio of L1 to L2 is greater than or equal to 0.4 and less than or equal to 1. Further, the ratio of L1 to L2 is 0.6 or more and 1 or less.

Then under the certain prerequisite of required effective gear length, can make motor shaft 13 and whole motor shorten along the size of first direction, improved the motor along the compact structure nature of first direction, reduced the volume of motor, and then make electric tool along the size of first direction compacter.

In some embodiments, in order to integrally form the gear 1311 on the first portion 131 and the second portion 132, a milling, hobbing or gear shaping tool is usually used for machining, and in the above machining manner, a relief groove needs to be left at one end of the first portion 131 close to the second portion 132, so that the length L1 of the effective gear is greatly smaller than the length of the first portion 131.

Preferably, in this embodiment, the gear 1311 is formed on the first portion 131 through a cold extrusion process. The cold extrusion is a process of putting a metal blank into a die cavity of a die in a cold state, forcing metal to be extruded out of the die cavity under the action of strong pressure and a certain speed, so that an extruded part with a required shape, size and certain mechanical property is obtained, a gear 1311 on the first part 131 is subjected to the cold extrusion process, a tool withdrawal groove does not need to be arranged, and the structural compactness of a motor 10 for an electric tool is ensured. The process parameters of the cold extrusion of the specific gear 1311 may be adjusted according to various factors, such as the specific shape and material of the gear 1311, and are not limited in detail herein.

Alternatively, as shown in fig. 2, a reduction box housing 40 is provided in the body portion 20, and the reduction box housing 40 divides the body portion 20 into two parts, wherein the transmission assembly 30 is located at the front side of the reduction box housing 40, the motor 10 for the electric tool is located at the rear side of the reduction box housing 40, and the motor shaft 13 penetrates through the reduction box housing 40 and enters the front side of the reduction box housing 40 and is connected with the transmission assembly 30. The mounting portion 1321 of the motor shaft 13 is supported on the reduction case housing 40 through a bearing 14. Further, the transmission assembly 30 includes a sun gear 31, a planetary gear 32 and an output shaft 33, wherein the planetary gear 32 is engaged with the gear 1311 on the motor shaft 13, the sun gear 31 is engaged with the planetary gear 32, the output shaft 33 is connected with the sun gear 31, and the output shaft 33 is connected with a tool outside the body portion 20. When the gear 1311 on the motor shaft 13 is rotated, the planetary gear 32 is rotated, and at the same time the sun gear 31 rotates the output shaft 33 to move the tool. Preferably, a shock absorption assembly 34 is further disposed between the output shaft 33 and the sun gear 31, so as to prevent the vibration of the tool from being transmitted to the motor shaft 13, and ensure the smoothness of the operation of the whole electric tool. The specific structure of the shock absorbing assembly 34 may be any one of the prior art, and is not limited herein. Of course, in other embodiments, the structure of the transmission assembly 30 is not limited to the sun gear 31 and the planet gear 32, and can be flexibly adjusted according to the needs.

Preferably, as shown in fig. 3, the fan 15 has a fitting portion 152 for fitting with the motor shaft 13 (third portion 133), and the fitting portion 152 may be connected with the motor shaft 13 by a bearing or the like. As shown in fig. 4, the side of the support ring 112 of the stator 11 facing the fan 15 has an end plate 111. Preferably, as shown in fig. 2, the matching portion 152 at least partially overlaps with the end plate 111 of the stator 11 along the first direction, so that the structure of the motor along the axis is more compact, and the axial size of the motor 10 for the power tool and the power tool can be further reduced. In this embodiment, the end plate 111 is an annular structure formed by multiple segments of surrounding space, and the radial dimension of the fitting portion 152 is smaller than the inner ring dimension of the end plate 111, so that the fitting portion 152 penetrates into the end plate 111 and approaches towards the rotor 12, thereby achieving at least partial overlapping with the end plate 111.

Preferably, as shown in fig. 3 and 4, the fan 15 has a third end surface 151 in the first direction, the magnet 121 of the rotor 12 has a fourth end surface 1211 in the first direction, and the third end surface 151 and the fourth end surface 1211 abut against each other in the first direction, so that the position of the magnet 121 in the first direction is limited, and the third end surface 151 and the fourth end surface 1211 abut against each other to make the structure of the electric power tool in the first direction more compact. Alternatively, in this embodiment, the third end surface 151 and the fourth end surface 1211 abut against each other, that is, the distance between the third end surface 151 and the fourth end surface 1211 is 0, and since the fan 15 and the rotor 12 are in a synchronous rotation state, no friction damage occurs between the third end surface 151 and the fourth end surface 1211. Of course, in other embodiments, the distance between the third end surface 151 and the fourth end surface 1211 may be greater than 0 but smaller, and is not limited herein.

Obviously, the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and for those skilled in the art, there may be variations on the specific embodiments and the application range according to the ideas of the present invention, and the contents of the present specification should not be construed as limitations to the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims (6)

1. A motor for a power tool, comprising:

a stator (11);

a rotor (12);

a motor shaft (13) connected to the rotor (12) so as to be rotatable together with the rotor (12), the motor shaft (13) including at least a first portion (131) and a second portion (132) in a first direction, the second portion (132) being provided with a mounting portion (1321) for mounting a bearing (14), the first portion (131) being formed with a gear (1311);

it is characterized in that the preparation method is characterized in that,

the second portion (132) is integrally formed with the motor shaft (13);

the effective gear length on the first portion (131) is L1, the bearing (14) is provided with a first end face (141) close to the gear (1311), the first portion (131) is provided with a second end face far away from the bearing (14), the distance between the first end face (141) and the second end face in the first direction is L2, and the ratio of L1 to L2 is greater than or equal to 0.4 and less than or equal to 1.

2. The motor for electric tools according to claim 1, characterized in that the gear wheel (1311) is formed to the first portion (131) by a cold extrusion process.

3. The motor for a power tool according to claim 1, further comprising a fan (15), wherein the fan (15) is fitted on the motor shaft (13) and disposed adjacent to the rotor (12), the fan (15) having a third end surface (151) in the first direction, the magnet (121) of the rotor (12) having a fourth end surface (1211) in the first direction, and the third end surface (151) and the fourth end surface (1211) being abutted in the first direction.

4. The motor for a power tool according to claim 3, characterized in that, in the first direction, a portion of the fan (15) for engaging with the motor shaft (13) at least partially overlaps with an end plate (111) of the stator (11).

5. A power tool comprising a body portion (20) and the motor for a power tool of any one of claims 1 to 4 mounted on the body portion (20).

6. The power tool according to claim 5, further comprising a power supply means detachably connected to the body portion (20).

Images